Variation in the electrophoretic karyotype analysed by the assignment of DNA probes in Candida albicans

Iwaguchi, Shin-Ichi; Homma, Michio; Tanaka, Kenji

doi:10.1099/00221287-136-12-2433

Cited by 118 publications

(116 citation statements)

References 28 publications

Supporting

Mentioning

113

Contrasting

Order By: Relevance

“…Iwaguchi et al (16) examined three strains of C. krusei and found that these organisms produced two bands between 2,000 and 3,000 kb and a single bright band between 1,200 and 1,600 kb that could not be resolved.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Karyotyping of Fluconazole-Resistant Yeasts with Phenotype Reported as Candida krusei or Candida inconspicua

Mata-Essayag¹,

Baily²,

Dw³

et al. 1996

International Journal of Systematic Bacteriology

View full text Add to dashboard Cite

The yeasts Candida krusei and Candida inconspicua have similar phenotypes, which may make discrimination of these organisms difficult. In this study we determined the karyotypes of 51 isolates of these two yeast species by contour-clamped homogeneous electric field electrophoresis. We found that the 43 isolates that had the C. krusei phenotype had three karyotype-specific characteristics. These isolates produced either two or three bands between 2,000 and 3,000 kb and no band between 1,300 and 2,000 kb, and there was either a single bright band at 1,300 or 1,200 kb or two separate bands at 1,300,1,200, or 1,100 kb. Using this technique, we were able to distinguish 27 different C. krusei types on the basis of band variations. The seven isolates identified as C. inconspicua on the basis of phenotype differed in that they produced at least one band between 1,300 and 2,000 kb. These isolates produced six to nine bands, in contrast to C. krusei strains, which produced three to six bands. The MIC of fluconazole for all of the isolates was at least 12.5 mg/liter, as determined by a broth dilution method.Candida krusei has recently emerged as an important opportunistic pathogen that causes infections, particularly in immunocompromised, critically ill, and human immunodeficiency virus (HIV)-positive patients (1, 4,8,13,15,21). When this organism is cultured from blood, the rate of mortality has been reported to be between 45 and 100% (6, 30). The increase in the rate of isolation of C. krusei may be due to the use of fluconazole both for prophylaxis and for treatment (1,4,13,25,32). C. krusei is resistant to fluconazole both in the laboratory and when the drug is used therapeutically (2,14).Isolates are identified as C. krusei strains on the basis of a set of phenotypic characteristics. These characteristics are sufficiently nondiscriminatory that in a clinical laboratory a member of a similar species, such as Candida inconspicua, could be misidentified as a C. knisei strain. The phenotypic characteristics used to identify C. krusei include colony morphology; the presence of pseudohyphae, true hyphae, and elongate blastoconidia; the absence of chlamydoconidia and germ tubes; surface growth that has the ability to form a climbing film on the sides of glass containers: glucose fermentation; assimilation of glucose, glycerol, DL-lactic acid, succinate, ethanol, and Nacetylglucosamine; lack of assimilation of galactose, L-sorbose, sucrose, D-ribose, L-rhamnose, maltose, cellobiose, trehalose, melibiose, raffinose, melezitose, inulin, starch, D-xylose, L-arabinose, D-arabinose, erythritol, ribitol, D-mannitol, salicin, inositol, lactose, galactitol, and glucosamine; failure to grow when potassium nitrate is the nitrogen source; and growth in a vitamin-free medium (28).C. inconspicua is distinguished from C. krusei by its failure to produce hyphae on corn meal agar, the presence of a primitive pseudomycelium, its inability to ferment glucose and assimilate N-acetylglucosamine, its ability to assimilate glucosamine, and its fai...

show abstract

Section: Discussionmentioning

confidence: 99%

“…Recent advances in molecular biology include the application of pulsed-field gel electrophoresis (PFGE) to the taxonomy of yeasts (3, 7,10,11,[16][17][18][19][20]24,26,30). Contour-clamped homogeneous electric field (CHEF) electrophoresis is a variant of this technique which improves chromosomal resolution (9).…”

mentioning

confidence: 99%

Karyotyping of Fluconazole-Resistant Yeasts with Phenotype Reported as Candida krusei or Candida inconspicua

Mata-Essayag¹,

Baily²,

Dw³

et al. 1996

International Journal of Systematic Bacteriology

View full text Add to dashboard Cite

show abstract

“…Medically important Candida species have been extensively studied (Asakura et al 1991;Iwaguchi et al 1990;Mahrous et al 1990;Rustchenko-Bulgac 1991;Snell & Wilkins 1986;Suzuki et al 1988). Chromosomal length polymorphisms have been observed in numerous species, and Rustchenko-Bulgac (1991) considers this phenomenon to be an important mechanism for increasing genetic variability of apomictic species.…”

Section: The Use Of Pulsed-field Techniques In the Systematics Of Yeamentioning

confidence: 99%

The use of karyotyping in the systematics of yeasts

Boekhout¹,

Renting

Scheffers

et al. 1993

Antonie van Leeuwenhoek

View full text Add to dashboard Cite

The use of electrophoretic karyotyping in systematics of yeasts is discussed. New data are provided on the karyotypes of the medically important fungi Hortaea werneckii, Filobasidiella (= Cryptococcus) neoformans, and Malassezia species. Hortaea werneckii has twelve to eighteen bands of chromosomal DNA, ranging in size between 500 and 2300 kb. The karyotypes of Filobasidiella neoformans consist of seven to fourteen bands of chromosomal DNA. The varieties neoformans and bacillispora cannot be separated by their karyotypes, and no obvious correlation was found with serotypes, geography or habitat. All strains of Malasseziapachydermatis studied have similar karyotypes consisting of five bands, whereas in M. furfur, four different karyotypes are prevalent. However, each of these karyotypes is stable.

show abstract

“…In this diploid organism, for which a sexual cycle has not yet been found, evidence supports clonal propagation, at least primarily (Pujol et al 1993;Lott et al 1999). Despite the asexual lifestyle, C. albicans shows frequent karyotypic variation (Iwaguchi et al 1990;Rustchenko-Bulgac 1991;Magee et al 1992). This could be problematic in a fungus that regularly undergoes meiosis (Kistler and Miao 1992).…”

mentioning

confidence: 99%

“…There are numerous reports of karyotypic diversity in C. albicans with chromosome size ranging from 4 Mbp to 0.5 Mbp (Snell and Wilkins 1986;Lott et al 1987;Magee and Magee 1987;Lasker et al 1989;Iwaguchi et al 1990;Asakura et al 1991;RustchenkoBulgac. 1991;Wickes et al 1991).…”

mentioning

confidence: 99%

Fine-Resolution Physical Mapping of Genomic Diversity in Candida albicans

Chibana¹,

Beckerman²,

Magee³

2000

Genome Res.

View full text Add to dashboard Cite

It has been suggested that Candida albicans, a diploid asexual fungus, achieves genetic diversity by genomic rearrangement. This important human pathogen may provide a system in which to analyze alternate routes to genomic diversity. C. albicans has a highly variable karyotype; its chromosomes contain a middle repeated DNA sequence called the Major Repeat Sequence (MRS), composed of subrepeats HOK, RPS, and RB2. RPS is tandemly repeated while the other subrepeats occur once in each MRS. Chromosome 7, the smallest of the eight chromosomes, has been previously mapped. The complete physical map of this chromosome was used to analyze chromosome 7 diversity in six strains, including two well-characterized laboratory strains (1006 and WO-1) and four clinical ones. We found four types of events to explain the genomic diversity: 1) Chromosome length polymorphism (CLP) results from expansion and contraction of the RPS; 2) reciprocal translocation occurs at the MRS loci; 3) chromosomal deletion; and (4) trisomy of individual chromosomes. These four phenomena play an important role in generating genomic diversity in C. albicans.

show abstract

Variation in the electrophoretic karyotype analysed by the assignment of DNA probes in Candida albicans

Cited by 118 publications

References 28 publications

Karyotyping of Fluconazole-Resistant Yeasts with Phenotype Reported as Candida krusei or Candida inconspicua

Karyotyping of Fluconazole-Resistant Yeasts with Phenotype Reported as Candida krusei or Candida inconspicua

The use of karyotyping in the systematics of yeasts

Fine-Resolution Physical Mapping of Genomic Diversity in Candida albicans

Contact Info

Product

Resources

About